U.S. patent application number 12/521999 was filed with the patent office on 2009-12-24 for mounting arrangement for fixing printed circuit boards disposed one above the other in a housing.
This patent application is currently assigned to CONTINENTAL AUTOMOTIVE GMBH. Invention is credited to Stefan Peck.
Application Number | 20090316377 12/521999 |
Document ID | / |
Family ID | 39431220 |
Filed Date | 2009-12-24 |
United States Patent
Application |
20090316377 |
Kind Code |
A1 |
Peck; Stefan |
December 24, 2009 |
MOUNTING ARRANGEMENT FOR FIXING PRINTED CIRCUIT BOARDS DISPOSED ONE
ABOVE THE OTHER IN A HOUSING
Abstract
A mounting configuration for a plurality of printed circuit
boards that are arranged one above the other and equipped with
electrical components. The printed circuit boards are fixed in a
housing assembly formed with a bottom and a top for receiving the
printed circuit boards. Engagement holes are positioned congruently
in the printed circuit boards, the housing bottom, and the housing
top, such that the printed circuit boards, the housing bottom and
the housing top can be fixed relative to one another by way of at
least one fastener.
Inventors: |
Peck; Stefan; (Dillingen a.
d. Donau, DE) |
Correspondence
Address: |
LERNER GREENBERG STEMER LLP
P O BOX 2480
HOLLYWOOD
FL
33022-2480
US
|
Assignee: |
CONTINENTAL AUTOMOTIVE GMBH
Hannover
DE
|
Family ID: |
39431220 |
Appl. No.: |
12/521999 |
Filed: |
January 2, 2008 |
PCT Filed: |
January 2, 2008 |
PCT NO: |
PCT/EP2008/050007 |
371 Date: |
July 2, 2009 |
Current U.S.
Class: |
361/801 |
Current CPC
Class: |
H05K 7/142 20130101;
H05K 1/144 20130101 |
Class at
Publication: |
361/801 |
International
Class: |
H05K 7/14 20060101
H05K007/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 9, 2007 |
DE |
10 2007 001 407.6 |
Claims
1-6. (canceled)
7. A mounting configuration, comprising: a housing assembly formed
with a housing base and a housing cover; a plurality of printed
circuit boards equipped with electrical components and disposed one
above the other in said housing assembly; said printed circuit
boards, said housing base, and said housing cover being formed with
engagement holes in mutually congruent positions, enabling at least
one fastening device to securely fix said printed circuit boards in
said housing assembly and to commonly fix said printed circuit
boards, said housing base, and said housing cover securely in
relation to one another.
8. The mounting configuration according to claim 7, which comprises
a spacer sleeve disposed between said printed circuit boards.
9. The mounting configuration according to claim 7, which comprises
threaded elements disposed on said printed circuit boards, for
meshing with said fasting device.
10. The mounting configuration according to claim 7, wherein said
printed circuit boards have a common format.
11. The mounting configuration according to claim 7, wherein said
fasting device is a screw fastener.
12. The mounting configuration according to claim 7, wherein said
fasting device is a plug-in element.
Description
[0001] The invention relates to a mounting arrangement for a
plurality of printed circuit boards disposed one above the other
and equipped with electrical components, said printed circuit
boards being fixed in a housing arrangement having a housing base
and a housing cover to receive the printed circuit boards.
[0002] As a result of increasing demands imposed on the
functionality of electronic control units in the field of engine
management, devices are increasingly being designed with a number
of printed circuit boards. In such cases conflicting requirements
are increasingly arising as regards the mechanical design. On the
one hand the electronics must be cooled effectively, meaning that
only narrow and not very variable gaps are able to be considered
for a thermal exchange layer. On the other hand the printed circuit
boards should not be deformed mechanically, in order to avoid
reliability problems resulting from broken components or
connections between components and printed circuit boards. Uniform
gaps for a thermal exchange layer can be realized by screwing the
individual printed circuit boards onto the heat sink in a defined
manner. However this means that a relatively large amount of space
on the printed circuit boards is used for the securing elements.
There are also layout-related restrictions to be considered because
of the numerous large through holes in the printed circuit boards.
If the number of connecting elements is reduced, it is necessary to
secure more than one printed circuit board with one connecting
element. Different tolerance chains then result in differing gaps
and thus also a differing thermal efficiency.
[0003] A system for the electrical contacting and mechanical
securing of printed circuit boards is known from DE 101 34 562 A1,
which features at least one cutting element or cutting and clamping
element to be positioned on the underside of a printed circuit
board and a securing element on the printed circuit board. In order
to ensure simple and fast assembly or disassembly, a support is
fixed with regard to at least one conducting wire in such a manner
that when the printed circuit board is mechanically secured with
the support by means of the securing element on the printed circuit
board, the conducting wire can be directly contacted by the cutting
element or cutting and clamping element on the underside of the
printed circuit board.
[0004] One disadvantage of the prior art is that securely mounted
printed circuit boards are deformed when subject to the action of
heat, which can damage the electrical components on the printed
circuit board or the electrical contacting. The fact that the
printed circuit boards are not supported in a stress-free manner
when subject to the action of heat also means that it is not
possible to guarantee a thermally optimized construction with
defined thermal exchange layers. Added to this is the fact that the
assembly space on the circuit board is significantly restricted by
the screw fixings.
[0005] Using this as its starting point, the object of the present
invention is to create a mounting arrangement for a plurality of
printed circuit boards disposed one above the other and equipped
with electrical components in a housing arrangement, which makes it
possible for the printed circuit boards to be supported in a
stress-free manner but in the process forms defined thermal
transition regions and requires little assembly space on the
circuit board.
[0006] This object is achieved by a mounting arrangement with the
features of claim 1. Advantageous embodiments and developments,
which can be used individually or in combination, are the subject
matter of the dependent claims.
[0007] The inventive mounting arrangement for a plurality of
printed circuit boards disposed one above the other and equipped
with electrical components in a housing arrangement is
characterized in that that engagement holes are disposed in
congruent positions in the printed circuit boards, the housing base
and the housing cover, so that the printed circuit boards, the
housing base and the housing cover can be fixed securely to and in
relation to one another by way of at least one securing means.
According to the invention provision is made for the printed
circuit boards, which are connected electrically and mechanically
for example by a press-in sleeve or preferably a spacer sleeve, to
be inserted onto a cooling surface provided in the housing cover.
The housing base, which likewise has a cooling surface, is then
positioned on the upper of the two printed circuit boards. A
securing means, for example in the form of a screw or plug-in
element, is then introduced by way of an opening in the housing
base and fixed to the housing cover through the upper printed
circuit board, the press-in sleeve and the lower printed circuit
board.
[0008] In a further embodiment provision is made for a printed
circuit board with a threaded element molded onto it to be secured
to the housing base by way of a threaded bolt and a second printed
circuit board with a threaded element molded onto it to be secured
to the housing cover. This embodiment also allows continuous
dissipation of the power loss by way of both housing parts. More
surface area is also available here on the printed circuit board
for the positioning of the electrical components.
[0009] By connecting the upper printed circuit board to the housing
base and by connecting the lower printed circuit board to the
housing cover it is possible to avoid a stepped arrangement of the
boards and both printed circuit boards can therefore be embodied
with approximately equal size. There is thus more board surface
area available for the positioning of electrical components. The
direct fixing of the press-in sleeve, which can be configured in
the form of a threaded element, to a board means that there is no
need for a connecting frame for the sleeves. This creates further
space on the board for the positioning of the electrical
components. It is also possible to dissipate the power loss by way
of both housing parts, with the result that the boards and
therefore the components and solder points are cooled more
efficiently. This requires sufficient pressure to be applied to the
boards, thereby ensuring optimal thermal connection.
[0010] The height tolerances of the cooling surfaces, the boards
and the threaded element are compensated for by way of a seal. One
further major advantage is that the securing means can have two
functions. On the one hand the securing means can seal the housing
and on the other hand it can fix the boards in the interior of the
housing. The functionality of the complete electrical system can be
tested before it is mounted in the housing. As a result it is
possible to carry out repairs or eliminate errors more simply
during manufacture.
[0011] The inventive embodiments have the further advantage that
position-dependency is reduced in that it is possible to access the
threaded bolt directly using the screw tool. It is also
advantageous that no screw feed is required. This solution means
that the board is no longer deformed during the fixing process, as
the normal force of the screw tool is applied directly to the
threaded bolt. This prevents the fracturing of solder points or
electrical components. The connection of the upper printed circuit
board to the housing base and the connection of the lower printed
circuit board to the housing cover means that a stepped arrangement
of the printed circuit boards is not required and both printed
circuit boards can therefore be embodied with approximately equal
size.
[0012] Further advantages and embodiments of the invention are
described in more detail below with reference to exemplary
embodiments and the schematic drawing, in which:
[0013] FIG. 1 shows a sectional diagram of a first exemplary
embodiment of an inventive mounting arrangement for fixing printed
circuit boards disposed one above the other in a housing;
[0014] FIG. 2 shows a perspective diagram of the exemplary
embodiment of the inventive mounting arrangement according to FIG.
1;
[0015] FIG. 3 shows a sectional diagram of a second exemplary
embodiment of the inventive mounting arrangement for fixing printed
circuit boards disposed one above the other in a housing.
[0016] FIG. 1 shows a sectional diagram of a first exemplary
embodiment of an inventive mounting arrangement 1 for fixing
printed circuit boards 2, 3 disposed on above the other in an
electronics housing that is preferably configured in two parts with
a housing base 4 and a housing cover 5. A press-in sleeve,
preferably in the form of a spacer sleeve 6, is disposed between
the printed circuit boards 2, 3. According to the invention
provision is made for the printed circuit boards 2, 3, which are
connected electrically and by the spacer sleeve 6 mechanically, to
be inserted onto a cooling surface 7 disposed in the housing cover
5. The housing base 4 with a cooling surface 8 is then positioned
on the printed circuit board 2. A securing means 9, preferably a
screw or plug-in element, is then introduced through a congruently
disposed engagement hole 10 in the housing base 4, in the printed
circuit boards 2, 3 and in the housing cover 5 and these components
are fixed to and in relation to one another. To compensate for the
height tolerances of the cooling surfaces 7, 8, the printed circuit
boards 2, 3 and the spacer sleeve 6 a seal is disposed 11 in these
regions.
[0017] FIG. 2 shows a perspective diagram of the exemplary
embodiment of the inventive mounting arrangement according to FIG.
1.
[0018] FIG. 3 shows a sectional diagram of a second exemplary
embodiment of the inventive mounting arrangement for fixing printed
circuit boards disposed one above the other in a housing. In this
preferred embodiment provision is made for the printed circuit
board 2 with a threaded element 12 molded onto the upper side, in
other words onto the side to be equipped with electrical
components, to be secured to the housing base 4 by way of a
securing means 9 and the printed circuit board 3 to be secured to
the housing cover 5 by way of a threaded element 12 disposed on the
lower side and a further securing means 9. The securing means 9 are
each inserted from the outside through a congruently disposed
engagement hole 10 in the printed circuit board 2 and in the
housing base 4 and/or in the printed circuit board 3 and in the
housing cover 5 and emerge respectively into the threaded elements
12.
* * * * *